91 Cherokee fuel pump buzzing.

My mom's 91 Sport's fuel pump is constantly buzzing now. Does that mean that it is about to take a crap on her or is this common. I never had the problem on my 93 Grand Cherokee. I think it might be ready to die but im not sure. Any help would be apprectiated

I've had a couple that buzzed, and couple that didn't. All of them never had a problem with fuel delivery. Should be fine?